2 Answers

Your cluster has been configured with less than 54GB and has only a Master, no Workers. 1 Worker is required. A single EC2 instance can support 54GB, so there are no additional EC2 costs incurred when you increase to 54GB.

To elaborate on the second problem identified above: we have a bug at the moment that allows you to create clusters without workers, and this prevents certain commands from executing.

You will know this is the case by checking in the clusters view, expanding the Nodes column, and confirming if there is at least one worker (note this doesn't apply to a special scenario we have in place for "mini" clusters used in classroom scenarios).

The effective minimum size for a cluster is 54GB, which is backed by a single EC2 instance, so you should resize your clusters to that value.